I searched MUD and found a link to a really nice write up on FJ40 horns by Coolerman...

That said, before I go off on a wild goose chase I figured I'd ask you all if maybe this isn't just a simple issue.

Background...My horns worked fine on my FJ40, until I started monkeying with stuff that is :mad:

I installed my Grant Security System and new Grant steering wheel, replacing my old Grant wheel. I followed the directions to the best of my ability and things seemed to go well. Had some issues with the roll pin for the signal cancellation but I think I got that figured out.

Anyway, I get everything installed, connect the battery back up and hit the horn and all I get is a week "brrrrrrrp" or just a click/thunk noise. WTF? Recheck the directions, connections, etc. etc. and nothing. I disconnect one horn and get a nice loud BLAST. Doesn't matter which horn is connected alone (high/low tone), I get the horn, but connect both at the same time and I get squat.

Any hints on what might be a simple solution to my problem?

SteveH

08-07-2007 12:30 PM

First, If you have a factory horn relay, remove the cover and inspect the contacts.

Otherwise, You may have a weak connection (either in the steering wheel area or elsewhere) that only allows enough current for one horn to work. Put a voltmeter on each horn as you blow the horns and see if you're simply not getting enough voltage (and ultimately current) to blow two horns at the same time. Try installing only the voltmeter in place of both horns to see what voltage the horns are seeing under no load. Then plug in one horn and measure at that horn, and at the other unplugged horn. Then plug in both and test at each horn. Test all reasonable combinations.

If you don't have a horn relay, consider adding one, using the power to operate the relay from the one horn. Run a wire to the battery, use a 30 amp relay, and you can power 4 horns from a Buick Park Avenue, if you like.

corsair23

08-07-2007 03:12 PM

Steve,

Thanks for the help! I looked for the horn relay last night and didn't see it so it so it is possible a PO removed it somewhere along the line. I am baffled why the horns worked before and not now but I'm sure it has something to do with the Grant Security System dropping the voltage.

By chance do you know where the horn relay should normally be located?

CardinalFJ60

08-07-2007 03:15 PM

PS fender

IIRC, it's on the PS fender in the engine bay. I had a dangling connecter right there

corsair23

08-07-2007 03:29 PM

Quote:

Originally Posted by CardinalFJ60
(Post 42886)

IIRC, it's on the PS fender in the engine bay. I had a dangling connecter right there

I'll look again for it but me thinks the PPO probably removed it :rant:

Oh well, I'll be one horn for awhile...Now, do I want to have the high tone or the low tone working :hill:

Shark Bait

08-07-2007 04:27 PM

I've got 3 sets of the newer style hi & low horns. I'm going to have to go check to see if I even have a horn relay in my project. :o

corsair23

08-07-2007 06:28 PM

From the linked web page above and per Shawn here is where to look :)

** Update 10-1-2004 I bought a pair of inner fenders from Ron Lang in Colorado Springs. On the passenger side was a GOOD horn relay! My horns do now blow! **

Shark Bait

08-08-2007 12:16 AM

I read all that and don't see the harness connector. Can anyone help me out with a picture of said horn relay in it's proper location? :confused:

SteveH

08-08-2007 11:56 AM

I have never found the horn relay in my '78 FJ - but I did find one on my '76 FJ55.

If anyone finds the location, please photograph it. To try to locate it, I disconnected both horns and never heard a clicking sound from under the hood, which would help you find the relay.

Shark Bait

08-08-2007 12:16 PM

Quote:

Originally Posted by SteveH
(Post 43047)

I have never found the horn relay in my '78 FJ - but I did find one on my '76 FJ55.

If anyone finds the location, please photograph it. To try to locate it, I disconnected both horns and never heard a clicking sound from under the hood, which would help you find the relay.

Thanks Steve. I'm wondering if maybe I don't have one either. I do have 2 wires to the horn locations on each side. I also have a socket up on the firewall and I have a relay in my box of stuff that looks like it would fit. It's not marked. I thought my wiring harness was '78 FJ40 and it may be. We'll see. I can post up pics. :eek: